CVE-2021-38296 Apache Spark Key Negotiation Vulnerability

What is CVE-2021-38296?

CVE-2021-38296 is a high-severity vulnerability in Apache Spark, published on 10 Mar 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Apache Spark supports end-to-end encryption of RPC connections via "spark.authenticate" and "spark.network.crypto.enabled". In versions 3.1.2 and earlier, it uses a bespoke mutual authentication protocol that allows for full encryption key recovery. After an initial interactive attack, this would allow someone to decrypt plaintext traffic offline. Note that this does not affect security mechanisms controlled by "spark.authenticate.enableSaslEncryption", "spark.io.encryption.enabled", "spark.ssl", "spark.ui.strictTransportSecurity". Update to Apache Spark 3.1.3 or later

Weakness: CWE-294

Which versions are affected by CVE-2021-38296?

6 open source packages ship an affected version, including org.apache.spark:spark-core, spark and pyspark. It affects 2 products.

Products include Apache Spark, Oracle Financial Services Crime and Compliance Management Studio.

How do I fix CVE-2021-38296?

Upgrade org.apache.spark:spark-core to 3.1.3 or later.

Is CVE-2021-38296 being exploited?

There is no known exploitation of CVE-2021-38296 in the wild and no public exploit code.

Other vulnerabilities in Apache Spark

• CVE-2022-33891 Apache Spark Command Injection Exploited High 8.8
• CVE-2020-9480 Improper Authentication in Apache Spark Critical 9.8
• CVE-2018-17190 Remote Code Execution in spark-core Critical 9.8
• CVE-2019-20445 HTTP Request Smuggling in Netty Critical 9.1
• CVE-2025-54920 Apache Spark: Spark History Server Code Execution Vulnerability High 8.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-spark-2021-38296, GHSA-9rr6-jpg7-9jg6, OESA-2022-1591, PYSEC-2022-186.